1 files changed, 4 insertions, 0 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index f560598807c1..42bd331ee0ab 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -80,6 +80,10 @@ void put_online_cpus(void)
         if (cpu_hotplug.active_writer == current)
                 return;
         mutex_lock(&cpu_hotplug.lock);
+
+        if (WARN_ON(!cpu_hotplug.refcount))
+                cpu_hotplug.refcount++; /* try to fix things up */
+
         if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer))
                 wake_up_process(cpu_hotplug.active_writer);
         mutex_unlock(&cpu_hotplug.lock);